Alberto Callaspo(7) celebrates with Craig Gentry, (3) after scoring the winning run on a Coco Crisp, (4) hit in the bottom of the 10th inning to end the game as the Oakland Athletics beat the Boston Red Sox 2-1 at the O.co Coliseum, in Oakland Calif. on Saturday June 21, 2014. Boston Red Sox pitcher Koji Uehara, (19) gave up the winning hit.

A's pitcher Luke Gregerson,(44) reacts to what he thinks is strike three in the 8th inning, but the umpire ruled a dropped ball by the catcher which ignited a fury of protests from the A's bench, as the Oakland Athletics take on the Boston Red Sox at the O.co Coliseum, in Oakland Calif. on Saturday June 21, 2014.

A's manager Bob Melvin continues to argue with home plate umpire Quinn Wolcott over the previous play in the 8th inning, as the Oakland Athletics take on the Boston Red Sox at the O.co Coliseum, in Oakland Calif. on Saturday June 21, 2014.

Coco Crisp, center (4) is swarmed by his teammates after his hit in the bottom of the 10th inning to end the game as the Oakland Athletics beat the Boston Red Sox 2-1 at the O.co Coliseum, in Oakland Calif. on Saturday June 21, 2014. Boston Red Sox pitcher Koji Uehara, (19) gave up the winning hit.

Boston cathcer A.J. Perzynski, (40) waits for the throw as the A's Stephen Vogt, (21) scores from third base on a fly ball by teammate Alberto Callaspo, (7) in the 3rd inning as the Oakland Athletics take on the Boston Red Sox at the O.co Coliseum, in Oakland Calif. on Saturday June 21, 2014.

Boston cathcer A.J. Perzynski, (40) waits for the throw as the A's Stephen Vogt, (21) scores from third base on a fly ball by teammate Alberto Callaspo, (7) in the 3rd inning as the Oakland Athletics take on the Boston Red Sox at the O.co Coliseum, in Oakland Calif. on Saturday June 21, 2014.

Then, with "Piederman" Josh Reddick on a rehab assignment, outfielder Yoenis Céspedes took over postgame pie duties and got the unsuspecting Crisp but good ... twice.

"I was kind of caught off guard. He got me with two of them!" said Crisp, who also drove in the go-ahead run in Friday night's 4-3 win. "He did a good job."

Callaspo was just the second A's player of the day to get past first base, moving to second on a sacrifice bunt by Nick Punto.

Without even being asked, Crisp raved about the bunt. "Guys are playing in, they know you're going to bunt and you've got Cayo at first so you have to lay down a really good bunt," Crisp said. "I wish there were (NBA-style) assists in this game. That would definitely be one heck of an assist right there."

At 47-28, the A's are a season-high 19 games over .500 and have the majors' top record. They have won five games in a row.

Things didn't look so rosy for Oakland in the eighth inning, though. With the potential tying run at third base, Luke Gregerson appeared to retire Boston's Mike Napoli on a caught foul tip to end the inning.

"It was pretty clear to everyone," Gregerson said. "It was pretty simple. All (home-plate umpire Quinn Wolcott) had to do was look at the ball, no scuff mark on it."

Wolcott thought that the ball hit the dirt, however. Crew chief Gerry Davis said that Wolcott had heard something - catcher Stephen Vogt's glove hitting the ground, Vogt surmised - and thought it was the ball. Because the ball was backhanded, first base umpire Greg Gibson didn't have a good enough view of the play to overturn it.

"My feeling is that if there's a play that needs to be reviewed, you should review it," Melvin said. "You just can't on that one."

Two pitches later, Gregerson threw a ball in the dirt that Vogt blocked - but it skipped a few feet in front of him and Dustin Pedroia raced home, a gutty decision that tied the game.

"The block got away from me maybe 2 feet - 2 feet further than it should have - and he made a great read," Vogt said.

When Napoli flied out to end the inning, Gregerson shouted his displeasure at Wolcott, and Melvin added in two more cents - and was tossed for his trouble.

A's starter Jesse Chavez, who usually has good control, tied his career high for walks (four) by the fourth inning, but he didn't allow a hit until the sixth, when Brock Holt and Pedroia had back-to-back singles to start the inning. Chavez then had to do some fancy maneuvering, getting David Ortiz to hit into a 3-6-1 double play and, with Holt at third base, striking out Napoli.

Like most of the A's starters, Chavez is heading toward a career high in innings pitched, and with two days off this week, the A's will skip one of those starters.

It won't be Chavez, though - signs point to Sonny Gray not pitching until the weekend series at Miami. Gray hasn't pitched a full season in the majors, and he leads the team with 99 innings.

Oakland's first run came in the third when Vogt hit a stand-up triple off the wall in right center and scored on a sacrifice fly by Callaspo. Vogt is 12-for-29 over his past 10 games.